Dental paste dispensing tool

ABSTRACT

A rotary dental tool is provided with self-contained means for automatically feeding a dentifrice to an applicator. The dentifrice is contained in an elongated tubular element that serves as a flexible coupling extending between a rotary drive and the tool head. During operation, the drive causes twisting of the tubular element, thereby urging the dentifrice toward the applicator.

United States Patent Myron F. Levenson 5596 Mayfield Road, Lyndhurst,Ohio 44124 Jan. 6, 1969 May 25, 1971 Inventor Appl. No. Filed PatentedDENTAL PASTE DISPENSING TOOL [56] References Cited UNITED STATES PATENTS2,789,352 4/1957 Wiseman 32/58 3,472,045 10/1969 Nelsen et al 32/59Primary Examiner-Robert Peshock Attorney-Bosworth, Sessions, Herrstromand Cain ABSTRACT: A rotary dental tool is provided with self-containedmeans for automatically feeding a dentifrice to an applicator. Thedentifrice is contained in an elongated tubular element that serves as aflexible coupling extending between a rotary drive and the tool head.During operation, the drive causes twisting of the tubular element,thereby urging the dentifrice toward the applicator.

DENTAL PASTE DISPENSING TOOL BACKGROUND OF THE INVENTION This inventionrelates to rotary dental tools and especially to cleaning and polishingtools for use with a dentifrice or the like. More particularly, theinvention has to do with a tubularcoupling element connecting the drivesystem and the applicator. The dentifrice is supplied to the applicatorfrom a reservoir in the tubular-coupling element.

An important part of modern professional dental care is the cleaning andpolishing of a patients teeth preferably using a prophylactic pastecontaining for example a fluoride to inhibit tooth decay. This is mostcommonly accomplished with a powered rotary tool having an angular bendor contra angle" as it is known in the art. The tool is held by thedentist and periodically dipped in a container of prophylactic paste.Frequent paste renewal is important even for cooling the teeth in viewof the frictional heat developed.

The need for periodically removing the applicator from the patient'smouth and dipping it in the paste is burdensome to the dentist andlengthens the period of time needed to complete a cleaning and polishingprocedure. Also, the paste after being in the patients mouth only ashort period of time becomes diluted by the patients saliva and a properconcentration of chemicals (such as fluoride compounds) may not beapplied to the teeth.-

While certain techniques for the continuous automatic feeding of dentalpaste to the tool head have been attempted, none have filled theprofessional needs of the dentist and none have been eflective toprovide a continuous unifonn supply of paste to the patierits mouth. Thedevice of the present invention, however, meets the long felt needdescribed above and affords other features and advantages heretofore notobtainable.

OBJECTS OF THE INVENTION It is among the objects of the invention tocontinuously feed a dental paste to the insert head of a dental toolduring a dentists cleaning and polishing procedure.

Another object of the invention is to reduce the time required toreplenish the dental pasteon the rotary head of the tool during thecleaning and polishing procedure.

Still another object is to provide a disposable tool insert of low costconstruction which serves as a paste dispenser for the cleaning andpolishing of a patients teeth.

These objects are accomplished by means of a dental polishing toolprovided as explained below with self-contained means for storing andfeeding a dentifrice to the tool head.

The tool includes a handpiece, preferably one taking the form of acasing of the contra-angle type. It is adapted to receive a disposableinsert equipped with a mandrel extending coaxially of the trailing endof the insert. The insert itself takes the form of a resilient, flexibleelement of tubular construction containing a charge of a dentifricesuch, for example, as dental paste. The mandrel with which the insert isequipped is designed to be rotated about its axis by a cooperating drivesystem.

An applicator of suitable type is attached to the other end of theflexible element. Rotation of the mandrel by the drive system twists theflexible element about its axis and reduces the interior cross sectionthereof. The result is to squeeze the paste out through the applicator.

According to one embodiment of the invention the dispensing of dentalpaste is assisted by means of a manually operated pressure element orshoe which is located in the carsing and which when depressed pushesagainst the flexible element to force paste out to the tool head.

According to another embodiment the flexible element is held in a hingedcasing formed by two semicylindrical halves which may be easily openedto replace the flexible element when desired.

FIG. I is a perspective view of a dentist's rotary polishing toolembodying the invention;

FIG. 2 is a longitudinal sectional view on an enlarged scale of thepolishing tool of FIG. 1;

FIG. 3 is a longitudinal sectional view of the flexible tubular elementcontained within the casing of FIG. 1 but shown in its unflexedcondition prior to insertion in the casing;

FIG. 4 is a much enlarged end elevation of the flexible element asviewed from the line 4-4 of FIG. 3;

FIG. 5 is a perspective view similar to FIG. 1 but showing a modifiedform of the invention;

FIG. 6 is an elevational view of the embodiment of FIG. 5

showing the hinged casing in its open position;

FIG. 7 is an elevational view on an enlarged scale of the embodiment ofFIG. 5 with parts broken away and shown in section for the purpose ofillustration; I

FIG. 8 is a transverse cross-sectional view on an enlarged scale takenon the line 8-8 of FIG. 7;

FIG. 9 is a fragmentary sectional view on an enlarged scale showing amodified form of the embodiment of FIGS. 5 to 8;

FIG. 10 is a transverse cross-sectional view on an enlarged scale takenon the line 10-10 of FIG. 9;

FIG. 11 is a longitudinal sectional view of a modified form of flexibletubular element embodying the invention; and

FIG. 12 is a longitudinal sectional view similar to FIG. 11 but showingstill another variation of the flexible tubular element.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring more particularly tothe drawings, FIGS. 1 to 4 show a rotary dental-polishing tool Aembodying the invention and adapted for connection to a rotary drive.The drive is transmitted by belts and pulleys through a mechanical armwith flexible joints as is customary in the art. The end of themechanical arm is shown in phantom lines in FIG. 1. Tool A has a tubularcasing 10 with an angular bend l1 (contra angle) which divides thecasing into a rearward leg 12 and a forward leg 11, the casing definingtherein a space for a flexible insert 14 with a mandrel 15 at one end, apolishing head 16 at the other end and a flexible resilient tubularportion intermediate its end which serves to transmit the rotary drivearound the angular bend 11 in the casing and which also serves as areservoir 17 for a charge 18 of dental paste.

The insert 14 is preferably formed of rubber or resilient plastic andhas a groove 19 at its forward end and a bearing groove 20 at itsrearward end. The groove 19 is adapted to receive a bearing ring 21formed inside the forward end of the casing 10 and the groove 20 isadapted to receive a bearing ring 22 at the rearward end of the casing10 to keep the angularly disposed ends of the insert in their properpositions during operation of the tool. The insert 14 is shown in itsnatural unflexed condition in FIG. 3, prior to its insertion in thecasing 10. FIG. 2 shows a cover 23 in phantom lines which may be used inconnection with the casing if desired.

In operation, the mandrel 15 is connected to a conventional drivespindle to transmit the rotary drive through the insert 14 to theapplicator 16. During the polishing operation friction between theapplicator and the teeth of the patient causes a high torsional load ininsert 14 and this in turn causes necking down or reduction incross-sectional size of the reservoir 17 thus putting a squeezing forceon the charge 18 of dental paste located within. This force causes agradual expression of the paste during the cleaning and polishingprocedure, charge 18 being of a volume calculated to serve the needs ofone patient.

Referring next to FIGS. 5 to 8 there is shown an alternative form B ofdental-polishing tool embodying the invention. The casing 30 in thisinstance is formed of two semicylindrical halves 31 and 32 connectedtogether at an integral hinge 33 best shown in the openposition-illustrated in FIG. 6. When the casing 30 is closed as shown inFIG. 5 the two halves 31 and 32 are latched together by integralclasp-type connections indicated by the numeral 34.

As viewed in cross section the embodiment of FIGS. 5 to 8 appearsgenerally the same as shown in FIG. 2 and the insert 14 within thecasing 30 is identical to that of the first embodiment.

As another aspect of the alternative form B of FIGS. 5 to 8, one of thecasing halves is provided with a dispensing button 35 located at the endof a lever arm 36 which is formed integrally with the casing 30 andwhich fits in a rectangular slot 37 in the casing wall. When thedispensing button 35 is depressed (FIG. 7) it bears inwardly against theresilient tubular wall of insert 14 and helps squeeze the paste outthrough applicator 16. With this arrangement the dentist may very easilyincrease the rate that the paste is dispensed by pressing the button 35with his thumb or finger during the cleaning and polishing procedure.

FIGS. 9 and show a variation of the embodiment of FIGS. 5 to 8 wherein adispensing button 40 is connected to a pressure shoe 41 located entirelywithin the casing 30 rather than to a lever 36 as shown in FIG. 7. Thebutton 40 extends through a rectangular opening 42 in the casing walland is initially positioned from the inside. This arrangement permitsdispensing pressure to be applied over a greater length of the insert14.

FIGS. 11 and 12 show alternate of an insert forms within the purview ofthe invention. FIG. 11 shows an insert 45 with a metal mandrel 46 havinga splined head 47 inserted in a matching socket 48 at the rearward endof insert 45. This arrangement is adapted for certain types of standarddental equipment. In the same FIG. is illustrated a variant whereincircumferential corrugations 49 are formed in the forward portion of theinsert. The corrugations provide improved flexibility for contra-anglebends of up to as much as 90, and at the same time assure a more uniformrate of bend with a reduced tendency to form a sharp crease at anyparticular location.

FIG. 12 shows still another insert 50 wherein applicator 51 is threadedinto the end of an intennediate body portion 52 and the lower end 53 hasa coupling fork connected to an interlocking mandrel 54.

It will be apparent from the foregoing description and drawings that byusing a dental tool embodying the invention, the need for periodicreplenishment of the dental paste at the tool head is eliminated and thecleaning and polishing procedure can be accomplished in a much shorterperiod of time with a much more uniform dispensing of dental paste tothe teeth during the procedure. Also, it will be apparent that theinsert is of simple low cost construction and can be economicallydisposed of after each operation. If desired, a

whole new casing may be coupled to the mechanical arm of the apparatusprior to work on each patient.

While the invention has been shown and described with respect tospecific embodiments thereof, this is for the purpose of illustrationrather than limitation and other modifications and variations will beapparent to those skilled in the art within the intended spirit andscope of the invention. Wherefore, the patent is not to be limited inany way that is inconsistent with the extent to which the progress inthe art has been advanced by the invention.

lclaim:

1. In a dental tool with self-contained means for storing a dentifriceand feeding it to the tool head, a handpiece taking the form of a casingof the contra-angle type; a disposable insert in the casing taking theform of an elongated rotatable element of generally tubular constructionthat is capable of flexing to conform to the shape of the handpiece;means in the tubular portion of the insert forming a dentifricereservoir that is closed at the trailing end and in open communicationwith the tool head at the leading end of the insert; a dentifriceapplicator at the leading end of the insert; and means at the trailingend of the insert for coupling it to a rota drive system whereby, whentorsional forces are exerted on e trarlrng end of the insert, thedentifrice in said reservoir is urged toward the tool head and out ofthe casing through said applicator.

2. Apparatusas defined in claim 1 wherein said casing is formed of twosymmetrical halves connected by a hinge to pennit opening of said casingfor removal and replacement of the insert.

3. Apparatus as defined in claim 1 wherein said casing has a slot formedin the sidewall thereof and extending therethrough and a pushbutton insaid slot extending outwardly from said casing and means operativelyconnected to said pushbutton within said casing for pressing against theinsert to express dental paste from said reservoir.

4. Apparatus as defined in claim 3 wherein said means connected to saidpushbutton is a lever arm integral with said cas ing and resilientlyconnected to said casing at one end at an end of said slot for pivotalmovement in said slot.

5. Apparatus as defined in claim 3 wherein said means connected to saidpushbutton is a pressure shoe adapted to bear against said couplingelement adjacent said reservoir.

' 6. A disposable insert for use in a hollow dental handpiece of thecontra-angle type wherein said insert takes the form of an elongatedflexible element of generally tubular construction that is suscepn'bleof bending to conform to the contraangle zone of the handpiece and ofindependent rotation within the handpiece while at the same time servingas a depletable dentifrice reservoir, said tubular element beingcharacterized:

a. at its leading end by an applicator through which the dentifrice maybe dispensed as needed,

b. at its trailing end by an axially projecting mandrel, and

c. by means therebetween for rotatably coupling the tubular portion ofthe insert to the interior of the handpiece.

7. A disposable insert according to claim 6 wherein the tubular portionof the insert is corrugated to enhance its flexiblity within thecontra-angle zone of the handpiece.

8. A disposable insert according to claim 6 wherein the applicator atthe leading end of the insert is formed integrally with the tubularportion of the insert.

9. A disposable insert according to claim 6 wherein the mandrel at thetrailing end of the insert is formed integrally with the tubular portionof the insert.

10. A disposable insert according to claim 9 wherein both the applicatorand the mandrel are formed integrally with the tubular portion of theinsert.

1. In a dental tool with self-contained means for storing a dentifriceand feeding it to the tool head, a handpiece taking the form of a casingof the contra-angle type; a disposable insert in the casing taking theform of an elongated rotatable element of generally tubular constructionthat is capable of flexing to conform to the shape of the handpiece;means in the tubular portion of the insert forming a dentifricereservoir that is closed at the trailing end and in open communicationwith the tool head at the leading end of the insert; a dentifriceapplicator at the leading end of the insert; and means at the trailingend of the insert for coupling it to a rotary drive system whereby, whentorsional forces are exerted on the trailing end of the insert, thedentifrice in said reservoir is urged toward the tool head and out ofthe casing through said applicator.
 2. Apparatus as defined in claim 1wherein said casing is formed of two symmetrical halves connected by ahinge to permit opening of said casing for removal and replacement ofthe insert.
 3. Apparatus as defined in claim 1 wherein said casing has aslot formed in the sidewall thereof and extending therethrough and apushbutton in said slot extending outwardly from said casing and meansoperatively connected to said pushbutton within said casing for pressingagainst the insert to express dental paste from said reservoir. 4.Apparatus as defined in claim 3 wherein said means connected to saidpushbutton is a lever arm integral with said casing and resilientlyconnected to said casing at one end at an end of said slot for pivotalmovement in said slot.
 5. Apparatus as defined in claim 3 wherein saidmeans connected to said pushbutton is a pressure shoe adapted to bearagainst said coupling element adjacent said reservoir.
 6. A disposableinsert for use in a hollow dental handpiece of the contra-angle typewherein said insert takes the form of an elongated flexible element ofgenerally tubular construction that is susceptible of bending to conformto the contra-angle zone of the handpiece and of independent rotationwithin the handpiece while at the same time serving as a depletabledentifrice reservoir, said tubular element being characterized: a. atits leading end by an applicator through which the dentifrice may bedispensed as needed, b. at its trailing end by an axially projectingmandrel, and c. by means therebetween for rotatably coupling the tubularportion of the insert to the interior of the handpiece.
 7. A disposableinsert according to claim 6 wherein the tubular portion of the insert iscorrugated to enhance its flexiblity within the contra-angle zone of thehandpiece.
 8. A disposable insert according to claim 6 wherein theapplicator at the leading end of the insert is formed integrally withthe tubular portion of the insert.
 9. A disposable insert according toclaim 6 wherein the mandrel at the trailing end of the insert is formedintegrally with the tubular portion of the insert.
 10. A disposableinsert according to claim 9 wherein both the applicator and the mandrelare formed integrally with the tubular portion of the insert.